Method of preparing alpha gas mixture suitable for substantially complete combustion



Oct. 18, 1932. H. FOERSTERLING METHOD OF PREPARING A GAS MIXTURE SUITABLE FOR SUBSTANTIALLY COMPLETE COMBUSTION Filed NOV. 11, 1927 F hoemfcoz MM K/a Patented Oct. 18, 1932 a :UNITED STATES;

PATENT OFFICE HANS FOERSTERLING, OF J'AMESBURG, NEW JERSEY; ROBERT J. MCNITT ADMINIS- TRATOR AD LITEM OF SAID HANS FOEBSTERLING, DECEASED,

METHOD or PREPARING A GAS MIXTURE SUITABLE FOR SUBSTAN'IIALLY COMPLETE COMBUSTION Application filed November 11, 1927. Serial No. 232,504.

This invention refers to an improved method of preparing a gas mixture suitable for substantially complete combustion and which can be made use of alsoin connection with 1: my co-pending application, Serial No. 139,-

87 4:, entitled Method of heating, filed by me on October 6th, 1926 and Serial No. 196,492, entitled Method of and apparatus for heating, filed by me on June 9th, 1927.

i..- The principal objects of my present invention are:

1st. To produce the proper mixture of a combustible gas and a combustion supporting gas for obtaining substantially complete com- T bustion with the least amount of expenditure.

Fig. 1 shows a diagrammatic view of the for diffusing the gas and air to form principal features of one form of apparatus required for carrying out my invention embodying generally a driving gas blower, an air blower driven thereby and suitable means a comoustible air gas mixture; and

Fig. 2is a diagrammatic view of my apparatus substantially embodied in Fig. 1, in connection with the recovery of the waste heat.

It will now however be clearly understood that my invention is not limited to the specific apparatus shown in these figures and the latter shall only serve the purpose of illustrating 3 specific manner of carrying out my invention.

Referring now to Fig. 1, 1 represents a gas main, in which a combustible gas is under considerable pressure; 2 represents a branch pipe from the main 1; 3 and 1 are pressure reducing and regulating devices, each havof the gas than has been heretofore ing a gauge for indicating the pressure in the main and the reduced pressure respectively. 5 is a connecting pipe leading the combustible gas to a positive blower 6, such as for instance a driving gas blower, the combustible gas after having passed through the blower is lead through pipe 7. 8 represents a stufling box for the shaft of blower 6, which is connected to the shaft of a larger positive blower 11 by means of the adjustable coupling 9. Blower 11 is provided with a stufling box 10, and has an intake pipe 12 and a discharge pipe 13. The combustible gas pipe 7 and the air pipe 13 combine in the diffuser .14 whichis provided with a screen of gauze of fine mesh.

The air and gas mixture leaves the difluser 14 through the pipe 15 and is conducted by the pipe 15 to the heterogeneous burners 16 and 18, which are provided with the valves 17 and 19. I

The function of the pressure reducing and regulating device is to insure that the pressure existing in the main is always greater than in the branches regardless whether much or little gas isdrawn and that the pressure of the'gas leaving the regulating device is uniform and suflicient to drive the two blow ers. 4

The functions of the driving blower 6 are to expand the combustible gas and to transmit the energy produced by the expansion to the shaft of the air blower 11.

The function of the driven blower 11 is to deliver such an amount of air that it is substantially sufficient for the complete com bustion' of the amount of combustible gas delivered in the same period of time by the driving blower.

The function of the diffuser is to mix the combustible gas and the air and prevent back firing.

I will now describe one method of carryingout my invention assuming that the combustible gas is illuminating gas which has been previously compressed to such a pressure that large quantities of gas can be distributed through comparatively small mains. The pressure of the gas coming from the main 1 and passing through the branch 2 will be slightly reduced through the pressure reducing and regulating device 3 and 4 but its pressure will be still sufficient to drive the blowers 6 and 11.

Upon opening the valves 17 and 19 of both of the burners 16 and 18, the internal pressure embodied in the gas contained in the main will cause a specific amount of gas to.

flow from the main 1 through the branch 2 and through the pressure reducing and reguating devices 3 and 4t and through the pipe 5 into the positive blower 6 in which it will expand and the internal energy contained in the compressed gas will be converted into power, while the expanded combustible gas will leave the blower 6 through the pipe 7. The power, thus recovered from the previously compressed gas, drives by means of the coupling 9,-the positive air blower 11,"

sucking air through the pipe 12'and delivering it through the pipe 13. Assuming now that the illuminatingga-s is of such a composition that the proper proportion of gas to air for effecting heterogeneous combustion in the burners 16 and 18 is 1 to 6, the blowers 6 and 11 will be so designed that operating under a uniform reduced gas pressure they will deliver per revolution of their shafts, gas and air in the proportion of 1 to 6. The exhaust of the blower 6, i. e., the illuminating gas, and the exhaust of the blower 11, i. e.,

air, are new mixed in the diffuser 1 1 which serves at the same time as a'safety device and the air and gas mixture can thus be burned heterogeneously in the burners 16 and 18. Instead of using an air blower having'a size six times as large as the gas blower, it'is obvious that two blowers of substantially equal capacity can be used by driving the blower by properly related gears or chain driven sprockets.

Instead of the heterogeneous burners 16 and 18, one homogeneous burner of suitable construction may be used.

Some of the principal advantages obtained through my invention are the following:

1. Whenever combustible gas passes through the first blower, the proper amount of the necessary air, 1. e., oxygen to make complete combustion is automatically added and mixed with it, insuring the proper heat efiiciency of the resulting air gas which is burned.

2. Introduction of heterogeneous combustionradiant heat gas can be carried to the location of consump- I tion in a comparatively small pipe, by pumping the gas into the main under sufficient ressure which means a lar er savin in investment and the power expanded for compressing the gas is recovered to a very large extent and made use of for driving the proportioning device, that is, the two blowers'which regulate the amount of gas and air to effect substantially complete com bustion. The recording of the gas consumed can be effected by providing the first blower with a suitable recording meter.

1 5. Existing gas plants can increase the output greatly without increase in investment of additional or larger pipes by installing a suitable compression system which will as- #5;

sure sufficient pressure to the main.

6. Distance transmission will now become possible for manufactured gases such as illuminating gas by using' higher pressure and suitable piping in the same way as is practiced at the present time with natural gas.

7. A process of mixing combustible air and gas preparatory to burning compressed gas such as for instance, compressed methane mixtures or compressed propane, etc, the energy contained in the already compressed gas is likewise recovered. l

8. In case the object to be heated is inflani' mable such 'as for instance varnish, tar, etc.. the burning of the same is precluded by using radiant heat by the use of a heterogeneous burner, since the gases resulting from the combustion, CO N and H 0 vapor will prevent ignition of the combustible heated object.

Referring now to Fig. 2, similarly as in Fig. 1, 1 represents the gas main in which combustible gas is supplied under consider able pressure; 2 is a branch pipe leadin from the main. 3 and 4 are pressure reducing and regulating devices with gauges for indicating the pressures of the main and the reduced pressures; 5 is a connecting pipe leading the combustible gas to the positive blower 6, such as for instance a Root blower.

7 is a pipe leading the gas from the blower to the place of consumption. 8 represents a stufling box for the shaft of the blower which is connected to the shaft of the larger blower 11 by means of the coupling 9. Blower 11 is likewise provided with a stufiing box an air intake pipe 12 and an exit pipe 20 represents an object to be heateda retort-set in a furnace 21, heated by the heterogeneous burner 22 and provided with a heat insulated conduit 23 for carrying off the hot waste gases. Conduit 23 leads to a flue at and a downtake pipe 25 open at the lower en and surrounded by a coil 26 which is conneeted at its upper end to the air pipe 13 and at its lower end to the heterogeneous burner 22. Coil 26 and downtake pipe 25 are surrounded by the heat insulated shell 27 provided with a conduit 28, the whole forming a heat exchanger or recuperator. Dampers 29 and 30 control the amount of waste heat which is passed into the heat recuperator. Pipe 7 conducting the combustible gas from the blower 6 to the heterogeneous burner 22 is connected to the latter by a union 31 to the short pipe 32 which passes through the burner 22 and terminates approximately in the center as shown in Fig. 2. The details of the construction of such a burner I have fully described in my aforesaid co-pendin application, Serial No. 196,492. Gas pipe% is provided with a gas cook 33 located near the burner 22.

The function of the downtake 25 andthe coil 26 is to recuperate a large part of the Waste heat leaving the furnace 21 and the function of the design of the burner 22 is to prevent preignition of the explosive mixture.

Assuming again that the combustible gas is illuminating gas and under sufiicient pres-. sure to carry out my process and that the blowers 6 and 11 are so designed as to furnish the correct gas and air mixture for effecting heterogeneous combustion, a balanced mixture will flow to burner 22, as soon as gas cock 33 is opened. After igniting the mixture heterogeneous combustion will set in quickly and retort will gradually be brought up to the desired temperature. Exhaust gases will leave the furnace through the heat insulated conduit 23 and as soon as the temperature inside of this conduit begins to rise these gases can be passed through the downtake by regulating dampers 29 and properly. The cold air coming from pipe 13 will then be preheated by passing through coil 26 and if coil 6 is of proper dimension, a large part of the waste heat of the furnace 21 can be recuperated, increasing thereby the efliciency of the heating system considerably as more fully described in my aforesaid copending application, Serial No. 196,492.

As already stated before it will be clearly understood that the apparatus described and shown in Fig. 2 shall only serve as one example to illustrate how waste heat can be recuperated with my method which is in no way restricted to the pre-he-ating of the combustion supporting gas-the airsince the.

combustible gas can be pro-heated in the same way by a second heat recuperator. Likewise the construction of the heat recuperator is inessential and can be modified in many ways also the construction of the burner.

Further my method can be applied to all kinds of objects to be heated. Liquids can be evaporated directly by an inverted burner, water and air can be heated to any desired temperature and the general method de scribed by means of the two figures can find numerous applications for domestic and industrial purposes.

Instead of illuminating gas, any other manufactured gas, such as producerwaterblast furnace gas, etc. can be used, or natural gas or compressed gas in cylinder form such as methane, propane, etc.

Whereas, I have described my invention by reference to specific forms thereof, it will be understood that many changes and modifications may be made without departing from the spirit of the invention.

1. A process of mixing combustible air and gas preparatory to burning which comprises passing gas under regulated pressureand volume through a suitable device driven by said gas, driving an air blower by said gas driven device at a rate correlated to the rate of said gas driven device, passing the air compressed by said air blower into a receptacle, leading the gas after delivery from said gas driven device separately from the compressed air into such receptacle to therein form an airgas mixture of predetermined relative proportion, leading such airgas mixture to a location of consumption and consuming the airgas mixture.

2. A process of mixing combustible air and gas preparatory to burning which comprises passing illuminating gas from a pressure main under regulated pressure and volume through a suitable device driven by said gas, driving an air blower by said gas driven device at a rate correlated to the rate of said gas driven device, passing the air compressed by said air blower into a receptacle, leading the gas after delivery from said gas driven device separately from the compressed air into such receptacle to therein form an airgas mixture of predetermined relative proportion and consuming the airgas mixture.

3. A process of mixing combustible air and gas preparatory to burning which comprises passing gas under regulated pressure and volume through a suitable device driven by said gas, driving an air blower by said gas driven device at a rate correlated to the rate of said gas driven device, adjusting the rate of delivery of said air blower to the rate of delivery of gas by said gas driven device. passing the air compressed by said air blower into a receptacle, leading the gas after delivery from said gas driven device separately from the compressed air into such receptacle l to therein form an airgas mixture of predetermined relative proportion, leading such airgas mixture to a location of consumption and consuming the airgas mixture.

4. A process of mixing combustible air and gas preparatory to burning which comprises passing illuminating gas from a pressure main under regulated pressure and volume through a suitable device driven by said gas. driving an air blower by said gas driven device at a rate correlated to the rate'of said gas driven device, adjusting the rate of delivery of said air blower to the-rate. of delivery I of gas by said gas driven device, passing the air compressed by said air blower into a re ceptacle, leading the gas after delivery from said gas driven device separately from the compressed air into such receptacle to therein form an airgas mixture of predetermined relative proportion, leading such airgas mixture to a location of consumption and consuming the airgas mixture.

In testimony whereof I have signed this specification this 7th day of November, 1927.

HANS FOERSTERLING. 

